If you use the shell extensively, I hope you know terminator by now. But, you know, this whole “writing a blog” thing will be pretty pointless if you already knew everything I wanted to say, so… I should probably elaborate.
For 1, look in the Profile tab, and the command tab. There you can set a custom profile to either exit (close), restart the command, or hold the terminal open.
For 2, by running a bash afterwards you replace the environment that the first command ran in. Something like: bash --rcfile <(echo ". ~/.bashrc && workon project") (Not sure if that will get mangled) will run source the bash rc, run the workon caommand, and crucially leave you in the same bash process.
These won't help with 3, and can't think of a solution right now.